'94 BMW 740i Not Running Correctly!
 

We have a '94 740i that to put simple, is nothing but a refined *****box. The car has had nothing but problems CONSTANTLY :mad:. I'm trying to sell the car asap and tonight I have discoved an unusual problem. The engine is beggening to miss terribly. The car feels like it's only running on 4 cylinders instead of 8 and the power output is horrible due to this. I drove the car for about 7 miles before bringing it back home, and as I got out of the car, phew! Something is burning!!! It really stinks like rubber/plastic. I also noticed that the exhaust is REALLY hot. When you put your hand on the back bumper, the bumper is almost too hot to touch. Also, you can feel a lot of heat radiating from the driver's side rear wheel area where the exhaust is. A lot of heat too... WTF is wrong with it now??? I've replaced oxygen sensors and motor mounts within the last 7K miles, so those should be ok. Can someone tell me what could be wrong? Better yet, can someone just take it off my hands?... I'll let it go for $4000.

I could list all of the other problems we have had, but I don't want to waste a lot of bandwith... ;) :mad:

Sounds to me like the spark coil pack, or whatever they call a coil now. Doesn't fire on several cylinders and dumps raw gas into the cat which burns in the cat. Pull the plug wires while running one at a time and see if you get spark. BTW, there is a BMW tech side of this board somewhere.

Thanks for the suggestions Hugh. I will take a look at that tomorrow. We've only owned the car for two years, so I think the engine block is original. It has 139K miles on it.

Do a compression check. Could be block failure.
Move the decimal place one place over to the left if it is a block failure $400.00

Ok, I took the coils off of the spark plugs and I found LOTS of oil in the spark plug well and the coils themselves were saturated in oil. Obviously, that is probably the problem. The coils were so saturated that they did not conduct electricity to the spark plug. The unusual thing is that the oil was on the top of the spark plug, so I don't think oil can be coming from the cylinders. Any thoughts?

Those V8's can suffer from valve cover gasket leaks. Clean everything up, then try to run it again. Also get someone with an OBD reader to check for OBD faults.

Didn't the famous nickasil cylinder failure only result in increased oil consumption and compression loss?